The present invention disclosed herein relates to an optical device, and more particularly, to a method and apparatus for measuring internal quantum efficiency of a light emitting diode (LED).
Generally, LEDs, which are being widely used as light sources, include the characteristics of small size, low power consumption, and high reliability. LEDs use chemical compounds such as AlGaAs, GaAlP, GaP, InGaAlP, and GaN. LEDs include an n-type semiconductor layer including chemical compounds, an active layer on the n-type semiconductor layer, and a p-type semiconductor layer on the active layer. LEDs, which are a sort of p-n junction diodes, are semiconductor devices using an electroluminescence effect in which monochromatic light is emitted when a forward voltage is applied. The wavelength of light emitted from an LED is determined by a bandgap energy (Eg) of a semiconductor being used.